Pack for applying therapeutic moist heat

ABSTRACT

A PACK FOR APPLYING THEREAPEUTIC MOIST HEAT CONTAINING A SORPTIVE MATERIAL BETWEEN A WATER AND WATER VAPOR PERVIOUS FABRIC SIDE PLACED TOWARD THE ANATOMY OF A PATIENT AND A WATER AND WATER VAPOR IMPERVIOUS MATERIAL, WHICH IS RELATIVELY ELASTIC AND STRETCHABLE COMPARED WITH THE FABRIC, FORMING THE OTHER SIDE OF THE BAG. THE MATERIAL OF THE OUTER SIDE OF THE BAG IS A GOOD HEAT INSULATOR AND IS MOLDED TO FORM A PLURALITY OF TROUGHS SO THAT, WHEN IT IS SEALED TO THE INNER SIDE OF THE BAG, USUALLY A FABRIC, A PLURALITY OF SEPARATE COMPARTMENTS HOLDING THE SORPTIVE MATERIAL ARE FORMED. STEAM OR WATER VAPOR CAN ESCAPE ONLY THROUGH THE FABRIC SIDE TOWARD THE ANATOMY OF A PATIENT AND HEAT LOSS ON THE OUTER SIDE OF THE BAG IS MINIMIZED. ALSO, THE ELASTIC, STRETCHABLE, MATERIAL OF THE OUTER SIDE OF THE BAG STRETCHES CONSIDERABLY MORE THAN THE FABRIC, THEREBY ENABLING THE FABRIC SIDE TO BE IN CLOSE CONTACT OVER MOST OF THE AREA OF THE FABRIC WITH THE ANATOMY OF THE PATIENT AND TO BEND TOWARD ITSELF ON A RATHER SMALL RADIUS. SO AS TO FIT CLOSELY AROUND THE BODY PARTS OF SMALL DIAMETER, SUCH AS SMALL WRISTS, ARMS. ANKLES AND LEGS.

United States Patent [72] inventor Jack M. Walker Chattanooga, Tenn.[21] AppLNo. 755,997 22 Filed Aug.28,l968 [45] Patented June28,l97l [73]Assignee ChattanoogaPharmacalCompany Chattanooga, Tenn.

[54} PACK FOR APPLYING THERAPEUTIC M OIST HEAT 8 Claims, 9 Drawing Figs.

[52] U.S.Cl 128/268, 128/402 [51] Int.Cl A6lj3/80 [50] FieldofSearch128/254, 258,268,399--403 56] References Cited UNITED STATES PATENTS437,994 10/1890 Jacobs 128/268 673,630 5/1901 Warner.. 128/268 914,9353/1909 Dunn 128/268 2,288,745 7/1942 Sammis 128/254 Primary Examiner L.W. Trapp Attorney-Lamont Johnston ABSTRACT: A pack for applyingtherapeutic moist heat containing a sorptive material between a waterand water vapor pervious fabric side placed toward the anatomy of apatient and a water and water vapor impervious material, which isrelatively elastic and stretchable compared with the fabric, forming theother side of the bag. The material of the outer side of the bag is agood heat insulator and is molded to form a plurality of troughs sothat, when it is sealed to the inner side of the bag, usually a fabric,a plurality of separate compartments holding the sorptive material areformed. Steam or water vapor can escape only through the fabric sidetoward the anatomy of a patient and heat loss on the outer side of thebag is minimized. Also, the elastic, stretchable, material of the outerside of the bag stretches considerably more than the fabric, therebyenabling the fabric side to be in close contact over most of the area ofthe fabric with the anatomy of the pa tient and to bend toward itself ona rather small radius, so as to fit closely around the body parts ofsmall diameter, such as small wrists, arms, ankles and legs.

PATENIED JUN28I97! 3' 587,578

\ r EFFECTIVE INVENTOR INEFFECTIVE Walk" BY 1, l0 2030405060 TIME (MIN)8 An NEY BACKGROUND OF THE INVENTION Moist heat has therapeuticsuperiorities for a wide variety of conditions, such as neuromuscular,strains, sprains, arthritic conditions, post-surgery problems,orthopedic conditions, etc.

Packs or compresses to be heated in boiling water have been madeheretofore of fabric. See, for example, Jensen U.S. Pat. No. 2,710,008.Up until now, steam packs, as they have been manufactured for years,have consisted of a two sided fabric envelope, one size ofwhich beinginches X 12 inches in outer dimensions, sewn into sections in aquiltlike fashion, with a small amount of bentonite, about 1 ounce, ineach of these sections. This bentonite filler readily adsorbs a largevolume of water when a steam pack is immersed in water. Thus, whenimmersed and heated in water, the tremendous adsorptive power'of thebentonite gel filler adsorbs and holds the water in a suspension,preventing it from running and dripping from the hydrated,water-swollen, mass. This amorphous mass inside each section has aconsistency similar to that of tooth paste. Actually, this material,when hydrated in a steam pack in this fashion, consists of around 80percent water. The two fabric sides of the envelope of theseconventional steam packs are of a weave sufficiently tight to preventthe hydrated gooey mass from escaping, but are still porous or perviousenough to permit the hot saturated air or steam to escape through thefabric. This is the principle of applying moist heat to the flesh of anarea being treated. Normally, layers of Turkish toweling will beinterposed between the heated steam pack and the flesh of the area beingtreated. Steam from the heated steam pack readily passes through theTurkish toweling, and reaches the flesh of the area being treated. Thesetowel layers serve as spacers, and can be added or removed, to vary theapplied heat according to the needs and tolerance of the patient and hisparticular condition.

A limitation of that type of compress is that, as shown in FIG. 3 of theJensen patent, hydration of the sorbent material within the compartmentsof the compress causes the sorbent to swell and to bulge out thecompartments considerably on both sides of the compress, so that only asmall part of the compress comes into contact, either through Turkishtoweling or directly, with the anatomy of a patient. This reduces theeffectiveness of the heat. This extreme swelling of the fabric of theconventional steam pack is undesirable, for it creates a series ofridges toward the patient, which does not give a maximum treatmentsurface. Instead, only the high points of the convex sections are nearthe patient.

Also, the bulges being pronounced and close together, the compresscannot be bent around a part of circular cross section which is of smalldiameter, because the bulges bump into each other, are relatively rigidand prevent such bending of the compress into a circle of smalldiameter. In the case of the conventional steam pack, with convexswelling to both sides, it is difficult to form it ,into small diametersreadily for applying to small round areas like the wrist, small arms,small ankles, small legs, etc. 1

Since the conventional compress is made of fabric on both sides, atleast as much steam, water vapor and heat escape from the compress onthe side away from the patient as are transmitted on the inner side tothe patient. Thus, both sides of the fabric envelope or cover ofconventional steam packs, as they have been made and used for someyears, are ofa porous or pervious material, permitting the hot watervapor saturated air or steam to escape from the hydrated heated fillerthrough both sides of the heated steam pack. Thus, the heat in the packis lost at a relatively rapid rate. Also, the water vapor or steamescaping to the outside moistens outer towels, bed linens, bed clothing,etc.

Other heat-transfer packs for therapeutic use have their outer walls onboth sides made entirely of a plastic or rubber. This does not provideto the anatomy of the patient a true moist heat application and is notso effective therapeutically as is a moist heat application of steam orhot water vapor to the skin ofa patient in accordance with the presentinvention.-

2 SUMMARY OF THE INVENTION tely prohibits the escape of saturated air orsteam from the hydrated, heated, filler in that direction. This plasticside of the envelope is the side away from the patient. Also, and ofutmost importance, this plastic side reduces the escape of heat in thedirection away from the patient, adding to the duration of effectivenessand efficiency of the steam pack. Both of these results are tremendousimprovements in this products operation, function, and efficiency.

BRIEF DESCRIPTION OF THE DRAWING FIG. I is a plan view of a packembodying the features of this invention;

FIG. 2 is a cross-sectional view showing one of the initial stages inthe manufacture of a pack made in accordance with this invention;

FIG. 3 is a cross-sectional view on the line 3-3 of FIG. 1 showing apack with its sorptive material in a dry condition, before it ishydrated;

FIG. 4 is a view similar to FIG. 3 showing a pack made according to thisinvention with its sorptive material in a wet swelled condition, afterit is hydrated, and in contact with the anatomy of a patient;

FIG. 5 is a view similar to FIG. 4 showing a pack of conventionalconstruction having both its sides made of fabric with its sorptivematerial in a wet swelled condition, after it is hydrated; and incontact with the anatomy of a patient;

FIG. 6 is a cross-sectional view showing how a pack made according tothis invention fits closely to the surface of a part of the anatomywhich is round in cross section and of small diameter, such as smallwrists, arms, ankles and legs;

FIG. 7 is a view similar to FIG. 6 showing how a pack of conventionalconstruction having both its sides made of fabric does not fit closelyto the surface over a wide area of contact but only at swelled up pointsof tangency and even then only around cylindrical body members ofrelatively large diameters; and

FIG. 8 is a graph showing approximately temperature against time for aconventional pack and for a pack made in accordance with this invention.

FIG. 9 is a cross-sectional view, similar to FIG. 2, showing a modifiedform of the invention.

DESCRIPTION OF THE PREFERRED EMBODIMENT There is shown in FIG. I of thedrawings a top plan view of a compress or pack embodying the features ofthis invention, the pack being generally indicated by the numeral 1. Thepack may be provided with suitable handling straps or loops 2, by whichit may be grasped for easy removal from or returning to boiling waterfor heating and by which it may be applied to the area of the anatomy tobe treated. The top surface, or side, 3 of the pack, i.e., the sidewhich is away from the anatomy ofa patient, is formed of a waterimpervious material which is flexible and elastic or stretchable. Suchmaterial may be one of a "number of different materials, such assynthetic rubber or various plastic n aterials including vinyl plastic,vin'yl resin, polyvinyl acetate, polyvinyl chloride, polyethylene andother related resinous materials.

The vinyl or other suitable material is vacuum formed or molded into aplurality of bulged sections or troughs 4, as shown in FIG. 2. Each ofthese sections forms a well or compartment into which is placed a smallamount, perhaps about an ounce, of dry aluminum silicate, bentonite gel5. Between the sections or troughs 4, the top side 3 is formed withrelatively narrow flat surfaces or ridges 6, which are on the same levelas the outer edges 7 of the top side.

A sheet of porous, woven, fabric 8 is next placed over the top side 3,while it is inverted, as shown in FIG. 2, for manufacturing purposes.The fabric 8 is then heat-sealed by a dielectric, high frequency,sealing tool, sealing only along the narrow raised ridges 6 and theouter edges 7 of the vinyl or other material, as shown in FIG. 3. Thiscompletely seals in the gel filler material and the steam pack is thenready for use.

When in use, the completed pack is immersed in boiling water or at leastvery hot water and heated in the same manner as heating is done of theconventional steam pack having two pervious fabric sides. The hot waterpenetrates the porous fabric 8, enabling the bentonite gel to hydratefully and to swell into an amorphous mass, as shown in FIG. 4.

Because the impervious side 3 of the pack is of an elastic, stretchable,material, heating and swelling of the bentonite gel causes the sectionsor troughs 4 to swell outward considerably, as indicated at 9, thisswelling out being on the side away from the patient's body. At the sametime, the fabric side 8, which is relatively inelastic, is swelledoutwardly, i.e., inwardly toward the body, only a relatively smallamount, as indicated at 10. The vacuum forming of the vinyl backing intoa series of bulges permits the swelling of the gel to occur toward theoutside, the side away from the patient, thus bulging out, i.e.,inwardly toward the body of the fabric on the patient side of thevarious sections is minimized.

To use the steam pack, it is lifted from the hot water bath, wrapped ina Turkish towel or in one of the specially designed terry cloth coverswhich are available, and applied to the patient. As shown in FIG. 4, thefabric sides 10 which are toward the anatomy of a patient, are bulgedout only relatively little and make heating contact, either throughTurkish toweling or directly, with the skin of a patient throughoutsubstantially the entire area of the fabric 8. With the improved steampack, there is only a slight bulge of the fabric on the patient side ofthe steam pack. In addition to the already formed bulges in the plasticbacking, the stretchability, or elasticity, of the plastic permitsfurther swelling in that direction, away from the patient. This resultsin a desirable improved effect, i.e., the swelling into convex ridges ofthe fabric toward the patient is minimized, exposing a more uniform,flatter, surface on the treatment side of the pack. Also, the imperviousside 3 of the pack, which is the side away from the patient, is a goodheat insulator and is impervious to water, water vapor or steam, so thatheat is not lost to any appreciable extent through that side.

In contrast to this, a conventional steam pack having both of its sidesmade of fabric is shown in FIG. 5 after it has been hydrated. From FIG.5, it will be seen that the hydrated and swollen conventional pack 11 isin contact with the body of a patient only at the relatively smallpoints of tangency 12 of the compartments of the pack. Thus, theconventional pack is much less efficient in transfer of heat from thepack to the body of a patient than is a pack made in accordance with myinvention.

Also, since the conventional pack has a fabric outer cover 13, aconsiderable amount of heat and water vapor or steam are lost throughthe outer side of the pack, away from the patient, so that a largeproportion of such heatis wasted and the conventional pack must beheated much more often than a pack made "in accordance with myinvention. To extend the duration of effective moist heat is of extremeimportance from standpoints of labor saving and efficacy. Many times, itis desirable to have an almost continuous moist heat application. Thus,the time intervals between the necessary replacings of a cooled steampack with a newly heated one are tremendously extended.

In addition, the conventional pack, allowing water or water vapor toescape, causes sheets, bedspreads, pillows, blankets, mattresses, bedclothing, etc., to become wet, to the discomfort and inconvenience ofthe patient and of the person attending him.

As shown in FIG. 6, a small body part of round cross-section, such as awrist, is shown in outline at 14. A pack made in accordance with thisinvention will be applied with the fabric side 8 toward the body of thepatient, and because of the relatively small amount of swelling of thefabric side at 10, after hydrating in hot water, the pack can be bentinto a circle of small diameter and can be brought with a large partofitsinner surface to bear upon the round body member.

In contrast, a conventional steam pack with both sides made of fabric isshown in FIG. 7 and it will be seen that, because of thebulging of thecompartments of the conventional pack on both sides, it cannot be bentin a circle of small diameter, so that it cannot be bend to make many ofits compartments 11 come into contact with the wrist 14, along the innercontact points 12 of the pack.

As shown in FIG. 8, a graph of temperature against time based uponactual experiment, it will be seen that the curve 15, which represents aconventional pack having both sides made of fabric, will remain at atemperature which is effective for therapeutic purposes only about 25 to30 minutes. In contrast, a pack made in accordance with the presentinvention, with an impervious, heat-insulating, outer surface and apervious fabric inner surface to be placed adjacent to the skin of apatient will, as shown by curve 16, remain at a temperature effectivefor therapeutic purposes about 40 to 50 minutes. Thus, it is clear thatthere is an increase in the duration of effective use of a pack made inaccordance with this invention over the duration of effective use of aconventional pack of up to 10 percent.

In FIG. 9, there is shown a modification of the invention in which thewater impervious side of the pack includes an inner layer of a flexibleand elastic water impervious material 3, as in the other form of theinvention, formed into bulged sections 4. There is also, next to theinner layer 3, an intermediate layer 17 ofa heat-insulating, closed cellfoam material, such as flexible polyurethane and an outside sheet 18 ofwater impervious material like that of the inner layer 3. Thisconstruction provides even better heat insulation.

It will be apparent to those skilled in the art that various changes maybe made in the invention, without departing from the spirit and scopethereof, and therefore the invention is not limited by that which isshown in the drawings and described in the specification, but only asindicated in the appended claims.

I claim:

1. A pack for use in applying therapeutic moist heat to an area of apatients anatomy comprising a water sorbent which will expand and sorb alarge volume of water, a water impervious material shaped with aplurality of outwardly extending bulges therein forming the outer sideof the pack and a sheet of flexible water pervious material which isrelatively inelastic compared with the water impervious material forminga substantially flat inner side of the pack in contact with the body,both the water pervious and the water impervious material beingimpenetrable by the sorbent and the sides being secured together toconfine the sorbent.

2. The article according to claim 1 in which the pervious material andthe impervious material are sealed together at appreciably spacedintervals to form compartments.

3. The article according to claim 1 in which the pervious material is afabric.

4. The article according to claim I in which the impervious material isselected from the groups of plastic materials including syntheticrubber, vinyl plastic, vinyl resin, polyvinyl acetate, polyvinylchloride, polyethylene and other related resinous materials.

5. The article according to claim 1 in which the water perviousinelastic material maintains contact with the anatomy of a patientthroughout substantially its entire area when the sorbent is hydratedwith hot water.

6. The article according to claim I in which the water perviousinelastic material is readily bendable about body portions of smalldiameter and maintains contact throughout substantially its entire areawith irregularities in the anatomy ofa patient when the sorbent ishydrated with hot water.

pack which will stretch and bulge out considerably away from the bodywhen the sorbent is hydrated, and a flexible water pervious materialwhich is relatively inelastic compared with the water imperviousmaterial forming a substantially flat inner side of the pack in contactwith the body and which will bulge inwardly toward the body very little,both the water pervious and the water impervious material beingimpenetrable by the sorbent and the sides being secured together toconfine the sorbent.

